The invention relates to motorcycle wheels, and more particularly to lightweight motorcycle wheels.
Motorcycle wheels are subject to a variety of forces during the operation of a motorcycle. The wheels are subject to normal riding forces that include the weight of the motorcycle and the forces caused by riding over bumps and potholes. The wheels are also subject to braking forces that are generated in the wheel when the brakes of the motorcycle are applied to stop the motorcycle.
If a wheel fails under such stress, the motorcycle may be rendered inoperable. It is therefore critical that the wheel be made sturdy enough to absorb the stresses encountered during the operation of a motorcycle. In an effort to prevent wheel failure, prior art wheels are constructed to be relatively heavy. A benefit of a heavier wheel is the potential for better tolerance for stress. A disadvantage of such heavy construction is added weight, resulting in diminished handling and reduced fuel efficiency for the motorcycle.
It is known to use disc brakes on a motorcycle. Disc brake assemblies include a disc or rotor mounted to a wheel, and a caliper positioned next to the rotor and capable of clamping onto the rotor to slow down the rotation of the associated wheel. Known motorcycle disc brake assemblies fall roughly into two categories. The first category includes a rotor mounted at the hub of the wheel and a caliper that clamps to the left and right faces of the rotor from the radially outer edge. This is the most common type of disc brake assembly used on existing cars and motorcycles. In operation, the braking force of the caliper and rotor is transferred from the hub, through the spokes, and to the rim of the wheel and the tire in order to bring the motorcycle to a stop. Braking forces have been historically transferred through the spokes of the wheel and therefore the spokes have been designed to withstand high stresses, usually resulting in solid spokes and heavier wheels.
The second category, a so-called xe2x80x9cinside-outxe2x80x9d assembly, includes a ring-shaped rotor mounted to the rim of the wheel along the rotor""s radially outer edge, and a caliper that clamps the right and left faces of the rotor from the radially inner edge of the rotor. During operation, the braking forces are no longer transferred through the spokes, but instead are transferred from the rotor directly to the rim. Therefore, the braking stresses are eliminated from the spokes and the spokes are capable of a more lightweight design that need only withstand the normal riding forces associated with the motorcycle.
The present invention provides a motorcycle wheel that includes a rim, a hub, and a spoke. The rim is adapted to receive a motorcycle tire, and the hub is adapted to receive and support a motorcycle axle. The spoke extends between the rim and the hub. The spoke includes first and second walls that are separated by a distance. The first and second walls are substantially entirely unconnected to each other between the hub and the rim.
The present invention also provides a motorcycle wheel that includes a rim, a hub, and spokes. The rim is adapted to receive a motorcycle tire, and the hub is adapted to receive and support a motorcycle axle. The hub defines an axis of rotation. A central plane of the wheel is perpendicular to the axis of rotation and substantially bisects the hub and the rim. The spokes connect the rim to the hub. The end of the spoke that is connected to the hub is substantially centered about the central plane, and the end connected to the rim is entirely on one side of the central plane.
Other features and advantages of the invention will become apparent to those skilled in the art upon review of the following detailed description, claims, and drawings.